Prime Minister Antonis Samaras warned before the vote late on Wednesday that without the bailout Greece would run out of money this month and face "catastrophe".

Many of these measures are fair and should have been taken years ago, without anyone asking us toAntonis Samaras, Greek PM

The austerity package - Greece's fourth in three years - is meant to close the nation's budget deficit, lower its huge debt burden and make its economy more competitive.

MPs must now pass a revised budget on Sunday before eurozone finance ministers meet next week to approve 31.5bn euros in fresh loans from the European Union (EU) and the International Monetary Fund (IMF) that Greece needs to avoid imminent bankruptcy.

But the level of resistance on the streets is a reminder that implementing the latest tough measures will be extraordinarily difficult, the BBC's Mark Lowen in Athens reports.

Samaras's warning

The crucial vote was held after a lengthy debate in parliament.

Immediately after the bill was adopted, co-governing New Democracy and Pasok parties expelled seven lawmakers from their ranks for failing to back the package.

The adopted plan includes a two-year increase in the retirement age from the current average of 65, as well as salary cuts and labour market reforms, including cuts to holiday benefits, notice periods and severance pay.

Workers fear this will just make it easier and cheaper for them to be fired at a time when unemployment has already soared to 25% and a five-year recession means there are few job prospects.

"Many of these measures are fair and should have been taken years ago, without anyone asking us to," Mr Samaras said.

"Others are unfair - cutting wages and salaries - and there is no point in dressing this up as something else," the prime minister said, adding that Greece was, nevertheless, obliged to take the measures.

Mr Samaras has said that without this money, which will be used largely to recapitalise the country's banks, the country will be bankrupt by 15 November.

'Mother of all strikes'

Earlier on Wednesday, tens of thousands of protesters held a rally in Syntagma Square - outside the parliament building in the heart of the capital.